Blood clots are an important function of your body that help control bleeding.  It is due to our clotting blood that we do not bleed out when we get a cut or have surgery.  Blood clots are made of platelets and fibrin.  Platelets are small colourless fragments of cells. Your bone marrow makes platelets.  Fibrin is a blood protein. Fibrin and platelets work together to seal off injured areas of your blood vessels.   Damaged blood vessels first line of defence are fibrin and platelets.

Unfortunately, blood clots can develop due to other reasons and can cause serious medical issues such as vein thrombosis, pulmonary embolism, and heart attacks.  Blood clots can develop due to being immobile for a long period or some medical conditions such as bleeding or blood clotting disorders.  Other factors such as being over 65 years of age, pregnant, obese, having cancer, taking birth control pills or hormones treatments, smoking, or lack of mobility can all contribute to blood clots forming.

Blood clots can be formed anywhere in your body.  Blood clots in your veins happen most frequently in your arms and legs.  This is deep vein thrombosis (DVT).  Blood clots that form in the arteries can appear in the lungs and is a pulmonary embolism.  Blood clots that block the flow of blood to your brain can cause a stroke, whereas blood clots in the heart may cause a heart attack.

The symptoms of a blood clot in your veins include swelling, pain, and a change in colour of your skin indicating possibly DVT.  Chest pain or shortness of breath can be symptoms of blood clots in your heart or lungs.

There are things you can do to help lower the risk of blood clots.  Getting an annual physical exam and participating in regular cancer screening is key.  As well as, being at a healthy weight, not smoking, staying hydrated, and staying active.  If you are using birth control, try using a non-estrogen alternative to birth control instead.

https://my.clevelandclinic.org/health/body/17675-blood-clots